Which of the following numbers is a factor of 104? ${6,10,12,13,14}$
By definition, a factor of a number will divide evenly into that number. We can start by dividing $104$ by each of our answer choices. $104 \div 6 = 17\text{ R }2$ $104 \div 10 = 10\text{ R }4$ $104 \div 12 = 8\text{ R }8$ $104 \div 13 = 8$ $104 \div 14 = 7\text{ R }6$ The only answer choice that divides into $104$ with no remainder is $13$ $ 8$ $13$ $104$ We can check our answer by looking at the prime factorization of both numbers. Notice that the prime factors of $13$ are contained within the prime factors of $104$ $104 = 2\times2\times2\times13 13 = 13$ Therefore the only factor of $104$ out of our choices is $13$. We can say that $104$ is divisible by $13$.